Wireless food safety monitor system

ABSTRACT

A wireless system for monitoring food safety having a monitor adapted to be disposed within a refrigerator. The monitor has a thermometer for measuring the temperature of the food within a refrigerator and a clock operatively communicating with the thermometer. The clock counts a time interval during which the thermometer detects at least a predetermined temperature communicating with the monitor. A communication signal, broadcasts an occurrence of the elapsed time exceeding a predetermined value. A receiving station within the broadcast area of the monitor, receives the broadcast elapsed time data and causes the occurrence of the elapsed time data to be transmitted across a cellular network to a remote device.

CROSS REFERENCE TO RELATED APPLICATION

This application claims priority to Provisional Patent Application No. 61/606,184 filed Mar. 1, 2012, and is incorporated herein as set forth in its entirety.

BACKGROUND OF THE INVENTION

This invention is directed to a device for monitoring temperature within a refrigerator, indicating to a user that the food has entered the danger zone for refrigerated foods, and more particularly, for continuously monitoring the conditions within the refrigerator and notifying a remote user of the status of the conditions within the refrigerator.

In this day and age, refrigerators are found in restaurants, places of work, produce stores and the like. Almost all foods are now stored in a refrigerator at one time or another.

However, refrigerators are subject to breakage, brown-outs, black-outs, and even improper closing providing unexpected rises in temperature over different periods of time. Even temporary loss of power in a refrigerator may lead to damage of foods contained therein.

As a result, the Food and Drug Administration (“FDA”) has determined a “temperature danger zone” of time temperature exposure for foods. The FDA has determined that whenever the temperature of a food subject to spoilage falls between 41° F. and 135° F. (5° C. and 57° C.) the food is within the “temperature danger zone”. The FDA has also set forth guidelines that foods cannot remain for more than four hours in the danger zone before they are no longer safe for consumption. A refrigerator must be continuously working properly for the temperature of its contents to be maintained outside the temperature danger zone.

In situations where the owner/operator or staff is away from the refrigerator, such as during a busy work day, when the restaurant is closed, or during brown-outs or black-outs, the operator of the refrigerator can only guess, if they are aware at all, as to whether or not danger zone conditions have been experienced by the food within the refrigerator.

One instrument for solving this issue is the inventor's refrigerated food safety monitor, as known from U.S. Pat. No. 7,360,369 which describes a food refrigeration monitor, including a thermometer and a clock for determining when the thermometer measures a temperature above a predetermined temperature corresponding to food spoilage. If the measured time is greater than a predetermined time value, an alarm is sounded. This device has been satisfactory, however it suffers from the disadvantage, that one must open the refrigerator in order to determine the current status of the time temperature clock, thus increasing the exposure of the refrigerator's contents to danger zone inducing conditions, and if one is away from the refrigerator, the alarm cannot be monitored.

Accordingly, a device which overcomes the shortcomings of the prior art is desired.

SUMMARY OF THE INVENTION

A wireless system includes food refrigeration monitor having a thermometer for measuring the temperature within a refrigerator and a clock for measuring the time during which the thermometer measures a temperature of the ambient environment. The monitor also determines a time during which the temperature is above a predetermined value. The monitor provides an output to a transceiver and sends one of a temperature signal at predetermined time intervals, and an alarm signal when an accumulated time value exceeds a predetermined value. A remote monitor includes a transceiver for receiving signals from the time temperature monitor and storing temperature data as a time stamped entry, the remote monitor providing an output to a cellular phone transceiver for transmitting the data received from the monitoring unit to a remote device.

In one embodiment of the invention, the remote monitor polls the food refrigeration monitor to determine current conditions within the refrigerator. The food refrigeration monitor undergoes the same conditions as the food, so the user may check the food temperature within the refrigerator at any time.

BRIEF DESCRIPTION OF THE DRAWINGS

For a fuller understanding of the invention, reference is had to the following description taken in connection with the accompanying drawing in which:

FIG. 1 is a schematic diagram of a system for monitoring food temperature in accordance with the invention.

DETAILED DESCRIPTION OF THE INVENTION

Reference is made to FIG. 1 which shows a wireless food safety monitor system, generally indicated as 100, constructed in accordance with the invention. Wireless food safety monitor system 100 includes a sensing unit, generally indicated as 10, which is disposed within the refrigerator to be monitored. Wireless food safety monitor system 100 also includes a receiving station 200 disposed locally to the refrigerator (within the same facility or at least within wireless communication range of sensing unit 10), but outside of the refrigerator and is in communication with sensing unit 10 as well as a portable communication device.

Sensing unit 10 includes a time temperature sensor 12. Time temperature sensor 12 such as that disclosed in Applicant's U.S. Pat. No. 7,360,369, which is incorporated herein in its entirety, includes a thermometer 13 encased in a housing for mimicking a temperature experienced by the food in the same environment as sensing unit 10 to measure the temperature of the food within the refrigerator, to provide a temperature output. In a preferred, but non-limiting example, sensor 12 may include a clock 15 for measuring time as known in the art.

Thermometer 12 continuously samples temperature within a refrigerator and outputs the measured temperature value. The clock 15 is a time interval clock which receives the temperature value from thermometer 13 and counts a time interval in response to the temperature sensed by the thermometer 13 of sensor 12 being above a predetermined temperature, such as 41° corresponding to the “temperature danger zone”. In this way a total time of temperature exceeding the predetermined temperature as sensed by sensor 12 is counted. Sensor 12 provides a temperature and/or a time temperature output to a microcontroller 14.

Microcontroller 14 may also have a clock thereon as known in the art and may poll sensor 12 for its temperature data, or time temperature data at predetermined intervals, such as every ten minutes, every half hour or some appropriate interval for monitoring changes in temperature within the refrigerator environment. Microcontroller 14 also determines whether the time temperature value monitored by sensor 12 has exceeded a predetermined value indicating that the temperature has been in the “temperature danger zone” for a sufficient time to indicate potential or actual food spoilage; i.e., in time to provide a preemptive warning, or to indicate a temperature violation. As a function of such determination, microcontroller 14 outputs a report signal to a transceiver 16 which is coupled to an antenna 18 to broadcast an alarm condition indicative either that spoilage may have occurred, or may occur if preventive action is not taken.

In other embodiments of the invention, microcontroller 14 may also report the monitored temperature at predetermined time intervals to transceiver 16 causing the temperature data to be broadcast by antenna 18 on a periodic basis. In one non-limiting exemplary embodiment, antenna 18 may be a radio frequency (RF) module, but may be any antenna capable of communicating directly with other devices, including receiving station 200 or known portable devices.

Sensor 12, microcontroller 14 and transceiver 16 are low voltage devices which are run by battery from a voltage regulated power source 20.

The signal produced by antenna 18 is a low power signal which is transmitted to receiving station 200, a pager, or other devices. Accordingly, a receiving station 200 is placed in the proximity of sensor 10, but outside of the refrigerator environment (the broadcast area). Receiving station 100 receives the signal from antenna 18, processes the signal as discussed below, and then transmits a report or alarm to one or more addressed mobile device, (not shown) such as a pager, tablet, or cell phone, carried by a person interested in the condition of the refrigerator.

More specifically, receiving station 200 includes a microcontroller and database 202. In a preferred non-limiting embodiment, the database and microcontroller are formed as a single unit 202. However, it is well understood in the art that a memory chip, separate from the microcontroller chip, may be used without departing from the spirit and scope of the invention. Microcontroller 202 is coupled to an antenna 204 by a receiver 206 for receiving the signals produced by antenna 18. Microcontroller 202 may also communicate with other devices by an Internet connection at Internet port 209.

Microcontroller 202 also receives a clock signal from an oscillator 208 as well as a real time signal from real time clock 210. Microcontroller 202, using these signals, may calculate a lapsed time as well as actual time in order to determine intervals and time stamps for monitored events.

Receiving station 200 also outputs data and messages to remote communication devices such as telephones, tablet computers, pagers, smart phones, laptops or the like. These remote devices may or may not be at the facility or in situ with the refrigerator being monitored, but utilizing system 100 allows continual monitoring by staff without the need to be continually at the facility with the refrigerator. Accordingly, microcontroller 202, by way of non-limiting example, is operatively coupled to a GSM module 212 or DCMA or any other type of cellular signal under the control of a subscriber identity module (SIM) chip or card as known in the art. A voltage regulator 216 coupled to power supply and battery charger 222 powers GSM module 212 which outputs an address signal across antenna 213 for broadcast to the desired remote device.

The components of receiving station 200 may be portable or fixed and as a result are powered by a power supply and battery charger 222 which may receive power either from batteries 226 such as lithium ion cells or an AC wall plug 224. In a preferred, non-limiting embodiment, power supply 222 operates on a 3 volt to 9 volt input and produces 3 to 4.7 volts which may be converted by a voltage regulator 228 to a lower voltage for powering either microcontroller 202 or receiver 206.

Visual indicators such as light emitting diodes 220 are connected and powered by microcontroller 202. Light emitting diodes 220 controlled by microcontroller 202, may be of two or more colors to indicate a status such that one color such as green may indicate transmission of data from receiving station 200, another color such as amber may indicate the reception of data, and a third color such as red for a third light indicating diode 220 may indicate temperature violation.

During operation, in one exemplary, but non-limiting embodiment, microcontroller 202 is passive and receives either an alert or an alarm signal or the periodic temperature signal from monitor 10 at antenna 204. Microcontroller 202 then date stamps the data utilizing an input from real time clock 210, stores the data or outputs a status signal by triggering an output to GSM module 212 causing a broadcast of a signal across antenna 213 to a remote device.

For example, microcontroller 202 may be programmed, in one non-limiting example to always forward the report of a danger zone condition, such as temperature above a predetermined value such as 41° F. Microcontroller 202 may also always transmit the alarm corresponding to a determination of spoilage condition by monitor 10, and the receipt of a spoilage signal at receiving station 200.

On the other hand, microcontroller 202 may make use of time intervals as determined utilizing oscillator inputs from oscillator 208 to determine predetermined time intervals to trigger the output of an information data signal to GSM module 212 or any type of cellular signal or internet communication for transmittal across an antenna 213 even when there is no alarm condition. The information data signal may be the current temperature as determined by monitor 10, and a real time stamp. Microcontroller 202 may store a number of received temperatures, date and time stamp each as received, and then transmit the stored temperatures, at predetermined intervals, as a summary report.

It also should be understood, that microcontroller 202 may be an active element sending polling signals to monitor 10 causing microcontroller 14 to request information from sensor 12 to then be transmitted back to receiving station 200. It should also be understood that the GSM module 212 or CDMA or cellular signal or internet under the control SIM 214 or other microprocessor can be called by a remote device causing microcontroller 202, in response to a prompt, personal identification number, or other code from the remote device to dump the data stored in microcontroller 202 as a report to the remote device or poll monitor 10 to obtain a current status of the refrigerator.

It should also be well understood, that the functionality of system 100 may be split to varying degrees between receiving station 200 and monitor 10. By way of example, microcontroller 14 may be “dumbed down” or clock 15 of sensor 12 may be removed because microcontroller 202 may poll monitor 10 at predetermined intervals to determine the temperature and then utilize oscillator 208 as the clock to determine a total elapsed time at which the temperature sensed at sensor 12 was in the danger zone. As a result, almost all of the functionality may be moved to the receiving station 200.

By providing an elapsed time triggered monitor, capable of reporting to a receiving station which is capable of both storing data, or immediately reporting conditions to a remote device, a simple mechanism for allowing a user to recognize the proper operation of a refrigerator without the need to be in the same physical location as the refrigerator is provided. Most importantly, the device provides a quick, simple, automated way of determining in real time whether food contained within the refrigerator is unsafe, whether being physically monitored by the operator of the refrigerator or not, thus decreasing the risk of food poisoning, food spoilage, waste or the like.

Thus, while there have been shown, described and pointed out, novel features of the present invention as applied to preferred embodiments thereof, it will be understood that various omissions and substitutions and changes in the form and details of the disclosed invention may be made by those skilled in the art without departing from the spirit and scope of the invention. It is the intention, therefore, to be limited only as indicated by the scope of the claims appended hereto.

It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described and all statements of the scope of the invention, which, as a matter of language, might be said to fall therebetween. 

What is claimed as new and is desired to be protected by Letters Patent of the United States is:
 1. A wireless system for monitoring food safety comprising: a monitor for monitoring a temperature within a refrigerator, the monitor having a thermometer for measuring a temperature within the refrigerator and a clock operatively communicating with the thermometer, the clock counting an elapsed time interval, during which the thermometer detects at least a predetermined temperature; and a transmitter communicating with the clock for broadcasting an occurrence of the elapsed time exceeding a predetermined value; and a receiving station not disposed within the refrigerator, and disposed within a broadcast area of the monitor for receiving a broadcast occurrence of the elapsed time and transmitting the occurrence of the elapsed time to a remote portable device.
 2. The system of claim 1, wherein the receiving station includes a real time clock, the real time clock date and time stamping each broadcast received from the monitor.
 3. The system of claim 1, wherein the occurrence of the elapsed time is transmitting across a communication network.
 4. The system of claim 1, wherein the transmitter communicates with the thermometer and the receiving station polls the monitor at predetermined time intervals, the monitor transmitting temperature data to the receiving station in response to each poll.
 5. The system of claim 4, wherein said receiving station determines whether the temperature data corresponds to a temperature above a predetermined temperature, and determines a time interval for an amount of time between a first poll and a successive poll for each poll resulting in a temperature above the predetermined temperature.
 6. The system of claim 3, wherein the receiving station date stamps each temperature data received at the receiving station and stores the temperature data and date and stamp; and transmits the temperature data and date and time stamp stored at the receiving station as a report to the remote portable device.
 7. The wireless system of claim 1, wherein the monitor determines at least one predetermined time interval and transmits the temperature of the food within a refrigerator to the receiving station at the end of each of the at least one predetermined time intervals.
 8. A system for monitoring food safety comprising: a monitor for monitoring a temperature within a refrigerator, the monitor having a thermometer for measuring a temperature within the refrigerator and a clock operatively communicating with the thermometer, the clock counting art elapsed time interval during which the thermometer detects at least a predetermined temperature; a transmitter communicating with the clock and the thermometer for broadcasting at least one of the temperature and the elapsed time; and a receiving station not disposed within the refrigerator, wirelessly communicating with the monitor and disposed within a broadcast area of the monitor for sending a poll to the monitor, the monitor transmitting at least one of the temperature and elapsed time in response to the poll.
 9. The system of claim 8, wherein the receiving station determines whether the temperature data corresponds to a temperature above a predetermined temperature, and determines a time interval for an amount of time between a first poll and a successive poll for each poll resulting in a temperature above the predetermined temperature.
 10. The system of claim 8, wherein the receiving station date stamps each temperature received at the receiving station and stores the temperature and date and time stamp, and transmits the temperature and date and time stamp stored at the receiving station as a report to a remote portable device.
 11. A method for determining whether food in a refrigerator has experienced unwanted temperatures comprising the steps of: placing a thermometer within a refrigerator; providing an elapsed time clock in communication with the thermometer, the elapsed time clock counting an elapsed time during a time interval in which the thermometer measures a temperature above a predetermined temperature; accumulating the elapsed time intervals, and outputting an alarm signal to a receiving station when the accumulated elapsed time exceeds a predetermined value; and the receiving station being disposed within a broadcast area of the thermometer and clock, and transmitting the occurrence of the accumulated elapsed time to a remote portable device.
 12. The method of claim 11, wherein the receiving station date and time stamps each broadcast received from the clock.
 13. The method of claim 11, further comprising the step of transmitting the occurrence of the elapsed time to the remote portable device across a communications network.
 14. The method of claim 11, further comprising the step of the receiving station polls the thermometer at predetermined time intervals, the temperature being transmitted to the receiving station in response to each poll.
 15. The method of claim 11, further comprising the step of the receiving station polls the clock at predetermined intervals, the elapsed time being transmitted to the receiving station in response to each poll. 